title: Purification of functionalized quantum dots.
abstract: Semiconductor quantum dots (QDs) are fluorescent nanoparticles that can be used for biological imaging. Because of their brightness and photostability, which is far superior to those of organic dyes and fluorescent proteins, they can be detected at the single-particle level over long periods of time using standard fluorescence microscopy techniques. QDs can be conjugated to biomolecules and then used to track the motion of these molecules. Commercial, soluble QDs are available either unconjugated or functionalized with specific biomolecules. In the latter case, biomolecules such as streptavidin, Protein A, or antibodies are attached to the QD surface. Free biomolecules are often present in the QD solution, and these can be detrimental for live-cell imaging or other fluorescence assays. It is thus desirable to purify the functionalized QDs from these contaminating free biomolecules using size-exclusion chromatography. This article describes a simple procedure for purifying functionalized QDs using MicroSpin SR-400 columns.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Courty
authors.forename: Maxime
authors.initials: M
authors.lastname: Dahan
mesh_terms: D002498:Centrifugation / Q000379:methods*; D002845:Chromatography / Q000379:methods*; D003584:Cytological Techniques / Q000379:methods; D005456:Fluorescent Dyes / Q000302:isolation & purification*; D008856:Microscopy, Fluorescence / Q000379:methods; D045663:Quantum Dots / Q000378:metabolism*; D013194:Staining and Labeling / Q000379:methods
chemical_list: D005456:Fluorescent Dyes